The present disclosure relates to coding techniques for omnidirectional and multi-directional images and videos.
Some modern imaging applications capture image data from multiple directions about a camera. Some cameras pivot during image capture, which allows a camera to capture image data across an angular sweep that expands the camera's effective field of view. Some other cameras have multiple imaging systems that capture image data in several different fields of view. In either case, an aggregate image may be created that represents a merger or “stitching” of image data captured from these multiple views.
Many modern coding applications are not designed to process such omnidirectional or multi-directional image content. Such coding applications are designed based on an assumption that image data within an image is “flat,” that the image data represents a captured field of view in a planar projection. Thus, the coding applications do not account for image distortions that can arise when processing these omnidirectional or multi-directional images with the distortions contained within them. These distortions can cause ordinary video coders to fail to recognize redundancies in image content, which leads to inefficient coding.
Accordingly, the inventors perceive a need in the art for image formatting techniques that can lead to higher coding efficiencies when omnidirectional and multi-directional image content are coded for delivery to other devices.